397940 has 24 divisors (see below), whose sum is σ = 848232. Its totient is φ = 156800.

The previous prime is 397939. The next prime is 397951. The reversal of 397940 is 49793.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 258064 + 139876 = 508^2 + 374^2 .

It is a junction number, because it is equal to n+sod(n) for n = 397897 and 397906.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1922 + ... + 2118.

It is an arithmetic number, because the mean of its divisors is an integer number (35343).

2³⁹⁷⁹⁴⁰ is an apocalyptic number.

It is an amenable number.

397940 is an abundant number, since it is smaller than the sum of its proper divisors (450292).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

397940 is a wasteful number, since it uses less digits than its factorization.

397940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 307 (or 305 counting only the distinct ones).

The product of its (nonzero) digits is 6804, while the sum is 32.

The square root of 397940 is about 630.8248568343. The cubic root of 397940 is about 73.5539271352.

The spelling of 397940 in words is "three hundred ninety-seven thousand, nine hundred forty".